QNAP QBack-35S

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The QNAP QBack-35S as an external SATA backup drive enclosure that can aid in both the safety and mobility of data. We found it to be a reasonable product sabotaged by inadequate documentation.

Test procedure
A hard drive was selected from the compatibility list for this machine -- in this case a Seagate Barracuda 7200.10 (Model: ST3160815AS). We ran speed tests on this drive while directly connected to a desktop PC and compared the score obtained to the score when the drive was installed in the QBack device.

The PC was kitted out with an MSI motherboard, 2.0GHz Core 2 Duo CPU, and 2GB RAM. Files were read or written from/to a second SATA drive, a Samsung SP2504C. We tested maximum speeds with a single compressed file of 1.68GB and minimum speeds with a directory tree containing over 40,000 small files with a total size of 4.33GB. Testing was conducted on both SATA and USB connections and included access to both encrypted and standard partitions.

We also consider the useability and function range of the software accompanying this product and the quality of the documentation.

Design and features
The QBack is an external drive enclosure with a special interface and software which allow for drive encryption, and automatic file backup. Drives up to 1TB can be installed -- the manual gives a list of compatible devices.

The casing is mainly an attractive brushed metal in titanium grey, while the ends and stand are glossy black plastic. Power and HDD LEDs are present on the front panel. The device comes supplied with all necessary cables including a panel allowing egress of cables from the rear of your computer.

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The three "applications" are described with extreme brevity with a statement of which cable -- SATA or USB -- is required. However, the Hardware Installation section never mentions the SATA connection at all. Management of the drive, including automatic backups and unlocking a secure partition, requires the USB connection and high data-speeds require the SATA connection.

We suggest you leave both cables plugged in if you need an external drive with encryption. Otherwise you just need SATA for standard drive function or USB when using the device as a backup drive.

The software allows the user to apply password protection to a secure partition -- if required -- and also looks after backup procedures. Backups can be done automatically whenever changes are made and the USB cable is attached, according to a schedule or immediately on user request (there is a "one-touch backup" button hidden at the rear of the machine). Obviously the user can request recovery of data from the QBack when needed; including the ability to control if files are automatically overwritten. You can specify easily and exactly which folders are to be included in all backup procedures.

Automated backup and standard external storage functions are not compatible. The SATA connection overrides the USB connection and disables the ability to use the backup software.


Test Speed (MB/s) Percentage of direct speed
Writing Min: 5.24
Max: 56.5
Direct connection (SATA) Min: 5.24
Max: 56.5
Secure partition via QNAP (SATA) Min: 5.46
Max: 23.9
Public partition via QNAP (USB) Max: 25.0 44%
Secure partition via QNAP (USB) Max: 15.4 27%
Direct connection Min: 6.03
Max: 56.9
Public partition via QNAP (SATA) Min: 6.66
Max: 58.6
Secure partition via QNAP (SATA) Min: 4.42
Max: 38.1
Public partition via QNAP (USB) Max: 22.9 40%
Secure partition via QNAP (USB) Max: 11.4 20%

Performance-wise this product is good. Connecting to the public partition via eSATA gives read and write scores which are not significantly different from a standard, direct SATA drive connection.

Secure drive access is slower as we would expect; maximum write speeds can be halved in some cases and read scores can be reduced by a third. Backups via USB are significantly slower than SATA access speeds as you would expect. Public partition access can be reduced as much as 50-60 percent over standard SATA speeds and secure drive access is 50 percent slower again.

The manual for this device is awful. Data storage can be via SATA or USB depending on how the device is to be used, but the hows and whys are not clearly laid out in the set-up guide. The electronic manual is little better and furthermore we saw no clear method of accessing this -- we had to hunt through the software directory to find it. Setting up the device isn't difficult and there should have been no trouble producing half decent instructions.

If you wish to use this device for automatic backups and as a standard external drive, you may need to reboot the machine and/or restart the QBack software before swapping between functions. Otherwise, the software may claim that it cannot find the requested drive. Occasionally a file could not be found during read/write procedures, but it is possible that this was due to interference by third-party security software.

The price is only AU$99 -- remember that the price of a drive needs to be added when assessing the cost effectiveness of this product. The warranty is a basic 12 months. Online support via e-mail and instant messenger is also supplied.


Hard Drive Form Factor Compatibility 3.5"
Host Bus USB 2.0
Features shock protection
Power Device
Type power adapter
Nominal Voltage AC 120/230 V
Storage Controller
Interface eSATA
Interface Type eSATA
Form Factor external
Bus Type Hi-Speed USB
Expansion / Connectivity
Bays 1 x internal - 3.5"
Interface Provided
Qty 1
Software / System Requirements
OS Required Microsoft Windows Server 2003, Microsoft Windows Vista / 2000 / XP
System Requirements
OS Required Microsoft Windows Server 2003
Environmental Parameters
Humidity Range Operating 0 - 85%
Brand QNAP
Product Line QNAP
Model QBack-35S
Packaged Quantity 1
Compatibility PC
Interface Required
Connector Type 4 pin USB Type B
Expansion Slots
Type none
Expansion Bays
Type internal
Form Factor 3.5"
Form Factor (metric) 8.9 cm
Total Qty 1
System Requirements Details
Processor Type Pentium III

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